Microstructural Characterization of AGR-2 TRISO-coated Particle Buffer, IPyC, and Buffer-IPyC Interfaces

Mauseth, Tanner Jason [Idaho National Laboratory] (ORCID:0000000195740463); Teng, Fei [Idaho National Laboratory] (ORCID:0000000338329138); Dunzik-Gougar, Mary Lou [Idaho State University]; Cai, Lu [Idaho National Laboratory]; Stempien, John D [Idaho National Laboratory] (ORCID:0000000166320785); Pradhan, Arnold [Idaho National Laboratory]; Bawane, Kaustubh Krishna [Idaho National Laboratory]; Shah, Sohail [Idaho National Laboratory]; Bachhav, Mukesh [Idaho National Laboratory] (ORCID:0000000181046032)

DOE OSTI · 3029867

Microstructural Characterization of AGR-2 TRISO-coated Particle Buffer, IPyC, and Buffer-IPyC Interfaces

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Abstract

Investigating the microstructural, mechanical, and chemical behaviors of Tristructural Isotropic (TRISO) fuel particles is vital for its qualification and use in advanced reactors. Central to the study of TRISO particles is understanding the silicon carbide (SiC) layer's ability to confine fission products, with failure mechanisms linked to chemical degradation following mechanical degradation of the buffer and IPyC layers. Research has been done to quantify the micro-tensile properties of the buffer, inner pyrolytic carbon (IPyC), and buffer-IPyC interlayer regions and their interactions within both irradiated and un-irradiated TRISO particles. Techniques such as atom probe tomography (APT) and transmission electron microscopy (TEM) have also been deployed to examine microstructural defects and fission product distribution in detail. The goal is to understand layer delamination, establish connections between microstructure and mechanical attributes, and inform computational predictions of fuel performance. This work may help refine predictive models of TRISO fuel behavior and facilitating its certification for use in advanced reactors.

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11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS 36 - MATERIALS SCIENCE 42 - ENGINEERING 77 - NANOSCIENCE AND NANOTECHNOLOGY AGR-2 Atom Probe Tomography (APT)Focused Ion Beam (FIB)Transmission Electron Microscopy (TEM)TRISO

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Mauseth, Tanner Jason [Idaho National Laboratory] (ORCID:0000000195740463), Teng, Fei [Idaho National Laboratory] (ORCID:0000000338329138), Dunzik-Gougar, Mary Lou [Idaho State University], Cai, Lu [Idaho National Laboratory], Stempien, John D [Idaho National Laboratory] (ORCID:0000000166320785), Pradhan, Arnold [Idaho National Laboratory], Bawane, Kaustubh Krishna [Idaho National Laboratory], Shah, Sohail [Idaho National Laboratory], Bachhav, Mukesh [Idaho National Laboratory] (ORCID:0000000181046032). 2025-04-16. Microstructural Characterization of AGR-2 TRISO-coated Particle Buffer, IPyC, and Buffer-IPyC Interfaces. https://www.osti.gov/biblio/3029867

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